A tractor is a very versatile piece of equipment and one of its standard uses is to tow various implements and vehicles. One of the annoying features of the tractor use has heretofore been the problem of coupling or hitching the tractor to a vehicle to be towed, particularly if only the tractor operator is available for this duty.
The task involves backing the tractor to a rather exact location, dismounting, and raising and holding the vehicle tongue to a height required to engage the tractor draw bar. The operator then remounts the tractor and drives the tractor so as to bring the tongue and draw bar into exactly the right relation. The operator then dismounts the tractor and sets the hitch pin to complete the hitch. This is a difficult procedure when the tractor operator does not have visual contact with the hitch.
Pin hitches are used to couple implements, vehicles, trailers, and wagons to towing vehicles. These hitches have clevis members with holes accommodating removable pins used to connect the clevis members to tractor draw bars. Examples of pin hitches for coupling a tractor to a trailer and the like are described in the following U.S. patents.
Duty in U.S. Pat. No. 1,804,973 shows a trailer having a tongue supported in a horizontal position with a coil spring. The forward end of the tongue is guided with converging plates into a clevis. A pin couples the tongue to the clevis. Balzer in U.S. Pat. No. 2,478,736 shows a hitch having a funnel member for guiding a tongue into a cavity. A pin biased with a spring connects the tongue to the hitch. A latch moved by the tongue releases the pin allowing the spring to bias the pin to a coupling position. Benson in U.S. Pat. No. 2,671,673 describes a hitch having a converging guide ramp for directing a tongue into a clevis cavity. A coupling pin is guided by a lever into aligned holes in the clevis and tongue. Richman in U.S. Pat. No. 2,937,887 uses a trailer hitch and stand to couple a tractor to a wagon. The hitch has a ramp for directing a clevis attached to a tongue into engagement with a trigger. The trigger releases a spring biased pin which moves down to connect the clevis to the draw bar of the tractor. Rimmey in U.S. Pat. No. 3,421,780 shows a wagon tongue biased to a horizontal position with a coil spring. The forward end of the tongue is guided into alignment with a hitch pin. A spring biases the pin to a down hitch position. A cable is used to pull the pin to a release position.
These hitches use springs to bias the hitch pins to connecting positions and manually operated devices, as cables and levers, to move the hitch pins to release positions. In the event that the pins are not in alignment with the holes in the tongue, the springs cannot move the pins to their connecting positions. The operator dismounts the tractor and aligns the holes to allow the pins to drop to connecting positions. An object of the hitch of the invention is to obviate the problems of the prior clevis and coupling pin hitches.